Building Better Antioxidants: Virtual Screening, Synthesis, and Characterization of Multifunctional Small Molecules Combining Nrf2 Pathway Activation and Direct Antioxidant Activity

项目总结/文摘

PROJECT SUMMARY/ABSTRACT Uncontrolled oxidative stress contributes to the development of neurodegenerative and ocular diseases for which there are yet to be effective therapeutic interventions. The investigators have developed small molecules that exhibit significant antioxidant reactivity in biological assays through two mechanisms: direct reactivity with reactive oxygen species and catalytic activation of the Nrf2 pathway. The investigators will incorporate virtual screening, rational design, synthetic chemistry, and molecular biology methods to produce enhanced antioxidant small molecules and understand how the small molecules activate catalytic antioxidant pathways. New molecules produced from this project are expected to provide radical scavenging activity, metabolic stability, and permeability. We propose four mechanisms of achieving improvement in these features compared to parent molecules. Virtual screening will be used to identify what combination of these approaches will yield the most promising targets. Following synthesis of these targets, cellular models for neurodegenerative and ocular disease (e.g. cataracts) will be used to test for protection from oxidative stress. Molecules showing potent antioxidant activity will then be screened for metabolic stability and blood brain barrier permeability. Explorations will also be focused on uncovering the mechanism(s) through which our small molecules protect through catalytic activation of innate antioxidant pathways in biology (Nrf2). Cell lysates from models exposed to ROS will be evaluated for Nrf2 and its downstream genes including NQO1, HO-1, SOD, GPX, and Trx, for example. The relationship between Nrf2 and inflammation is also explored. This approach will identify the path(s) of protection each strategy of antioxidant enhancement provides and identify lead molecules to be explored further and proceed to future work involving animal toxicology, clearance, and activity assessment. Altogether, a comparative approach that uses data from chemical assays and biological studies will allow the investigators to identify molecules and moieties that provide the characteristics needed to serve as a therapeutic for neurodegenerative and ocular disorders arising from oxidative stress. This proposal takes a unique approach to targeting oxidative stress by using computational and synthetic chemistry to combine different reactive building-blocks into small molecules designed to have activity through targeting molecular features of neurodegeneration and diseases of the eye in a manner that is greater than the sum of the individual parts.